So I'm refining my group's house rules for SR4e, which at this point are a pretty extensive rewrite of the core rules (alt.War, EotM, etc).

Looking over foci, I have a couple of thoughts:
* Power foci are just bad for the game. They're boring and they encourage corpse looting (just for greyhawking, not for reuse). They're being house-ruled out.
* Sustaining foci are possibly bad for the game. The mage player likes them, because they're a power-up, but everyone else finds them a hassle. They make going through wards complicated and increase the risk of astral detection. They may get house-ruled out of the game.
* Weapon foci are okay. They should be open to everyone. We're house-ruling that non-Awakened can bond with weapon foci.

The other categories of foci are probably okay, though it's hard to get a good analysis because under standard rules, power foci are overwhelming better except for the one thing that sustaining foci do better.

Criticisms of the suggested house rules? Suggestions for a better implementation of foci that give mages something to spend their nuyen on but don't make mages stupidly powerful?